Date of Graduation


Document Type


Degree Type



School of Dentistry


Not Listed

Committee Chair

Peter Ngan.


Objectives. To evaluate the correction obtained from the Forsus Fatigue Resistant (FRD) device and orthodontic appliances compared to an untreated control group. Methods. Twenty four patients were treated with the Forsus FRD and fixed orthodontic appliances and were compared to twenty two untreated control patients who were matched in age, sex and craniofacial morphology. Lateral Cephalograms were taken before treatment (T1) and after Forsus FRD and removal of orthodontic appliances (T2). Results. Statistically significant differences were found for 12 of the 29 variables measured. Significant differences were found at Co-Gn minus Co-Apt., Wits, Is-OLp, Ii-OLp, overjet, Mi-OLp, Molar relationship, Overbite, Mic-ML, SNA, ANB, and Ii-ML between the treated and control groups. Linear measurements in the net position of the maxilla and mandible showed changes that included a reduction in maxillary forward growth and a stimulation of mandibular forward growth; however, these changes were not statistically significant. Net overjet correction was 4.7mm. 1.9mm (40%) of the correction was skeletal and 2.8mm (60%) was dental. Overjet correction was obtained by decreased maxillary growth (25%), increased mandibular growth (15%), retraction of the upper incisor (32%), and proclination of the lower incisor (28%). Conclusions. The Forsus FRD is successful in treating Class II malocclusions; however, there is a significant proportion of the correction which is dental in nature.